It works a lot like Hot or Not, allowing users to quickly judge each others' looks based on profile pictures. If both people find each other attractive, Tinder allows them to "match," then message back and forth to schedule a date.

The Los Angeles-based startup was founded by four entrepreneurs, Sean Rad, Justin Mateen, Jonathan Badeen, and Christopher Gulczynski, and it is backed by IAC, the parent company of Match and OKCupid.

In February Tinder was generating 10 million matches per day.

Here's how the $500 million dating sensation works.

When you open the app, it welcomes you with basic instructions.

If you like someone and they like you, it's a match! You're then allowed to message each other. If not, you go your separate ways and no feelings are hurt.

Tinder makes you sign in with Facebook, because it pulls your most recent profile photos and a few other tidbits for your dating profile on the app.